HAN Deqiang;DANG Yamin;XUE Shuqiang;WANG Hu;ZHANG Longping;CHAI Yanni;Chinese Academy of Surveying and Mapping;Beijing Research Institute of Telemetry;Shandong University of Science and Technology;Faculty of Geomatics,Lanzhou Jiaotong University;

In view of the uneven distribution of the BeiDou ground reference station,which affects the accuracy of BeiDou orbit determination,the grid based stochastic optimization method was adopted in this paper,taking account of the quality,distribution and station stability of the stations,the global distribution of MGEX stations was evenly selected.The weighted GDOP index was used to evaluate the effectiveness of the selected stations,and the influence of the number,distribution and quality of the stations on the orbit determination accuracy was comprehensively analyzed.The results showed that the precision orbit accuracy of GEO,IGSO and MEO satellites of BeiDou satellite was 221.56,12.59 and 6.81 cm respectively when 30 stations are selected by this method,there was a greater improvement than the grid method.Within a certain range,the more the number of stations was,the higher the accuracy of orbit determination was.